In my U.S. Pat. No. 4,255,612, issued on Mar. 10, 1981, entitled "Insulator for Covering Electric Cables," which is owned by the assignee of the present invention, there is disclosed a technique for insulating the joints between the conductors of two flat multiconductor cables. The specification of that copending application is incorporated into this specification by reference thereto herein.
Briefly, a series of joints between selected conductors of two overlapping flat multiconductor cables are formed using metallic connectors which extend beyond the surface of at least one of the cables. The bare metallic connectors in contact with energized electrical conductors themselves become electrically "hot" and can cause anyone who, directly or indirectly, contacts such connectors to receive a severe electrical shock.
In my earlier application, it was proposed to electrically insulate the connectors by covering them with a flat sheet of relatively flexible electrical insulation supported by an insulating spacer of a thickness sufficient to accommodate the protruding portions of the metallic connectors. The spacers, caused to adhere to the surface of the cables themselves, served to provide a sufficient insulation barrier to prevent tracking across the cable surfaces from connector to connector. This was true despite the large size of the holes in the insulator to accommodate the connectors regardless of their orientation.
The flat multiconductor cable constructed in accordance with the teaching in U.S. Pat. No. 4,219,928 issued to Kuo on Sept. 2, 1980 and owned by the assignee of the instant invention, and by this reference made a part hereof, have a series of parallel flat, insulated conductors separated from adjacent conductors by flattened depressed regions of insulation only which, due to the presence of a score line, lend themselves to tearing should it be desired to separate the conductors from one another. These flattened, depressed regions are significantly thinner than the adjacent conductor insulation portions of the cable. As a result, the relatively thick insulating spacers placed on the conductor insulation fail to conform to the depressed regions leaving pathways between the cable surface and the insulating spacers where moisture, dirt or other contaminants can enter. Due to the size of the holes in the insulating spacers, they often overlap the depressed regions permitting the connectors to be subjected to any moisture, dirt or contaminants contained therein, leading to a shorting of or other injury to the joints and cables.